I disagree. If it's the basic Bio course you did bad in, while upper level Bio courses you did good in, retaking the entry basic level Bio class doesn't really do much for you. For example if you get a C in bio 1, but get As in bio 3 4 and 5, does going back and retaking the easiest Bio class do much for you? It may boost your GPA but personally I would take a different class.Yep. You need a better than Cs in basic biology. Otherwise your foundation is so shaky that you can't build on top of it successfully. For a retake on something so basic and central to your future education you really should be shooting for strong replacement grades.